Pesticide in Telstra cables

There are further concerns about the safety of Telstra's telecommunication pits where for decades the Telco used the highly toxic chemical, Dieldrin to protect its cables.

Transcript

TONY JONES, PRESENTER: It's no longer just about asbestos. New concerns have emerged tonight about the safety of Telstra's telecommunication pits. For decades the telco used the highly toxic chemical dieldrin to protect its cables from pests. Unions allege that NBN Co was warned about the problem in 2010. Science and technology reporter Jake Sturmer reports.

JAKE STURMER, REPORTER: It's not just deadly asbestos lurking in Telstra's telecommunications pits; some contain the now-banned pesticide dieldrin. It was widely used in agriculture and in timber products and Telstra sprayed it on its cables to stop termites.

The toxic chemical has been linked with Parkinson's disease and can trigger comas.

Unions fear much like the asbestos scare, contractors working with the soil could have also been contaminated.

VALERIE BUTLER, CEPU VICTORIA: People have been working quite unsafely on the network and so their exposure to dieldrin would be a very real risk.

JAKE STURMER: Dieldrin is banned in most countries and was phased out in Australia in the early '90s. The chemical has a half-life of five years, meaning every five years its toxicity is halved.

Experts say exposure in telecommunications pits is unlikely to be as harmful as asbestos, but they're urging caution.

MALCOLM SIM, MONASH UNIVERSITY: There still could be a concern over insecticides in soil and they're very persistent, as I said, and they can accumulated in the body as well and that was the main reason for them being phased out.

JAKE STURMER: The union says it raised the asbestos and dieldrin concerns at a meeting with NBN Co in Melbourne in August, 2010.

VALERIE BUTLER: They certainly took note of that particular issue. I mean, once we've passed that information to them, we expected and do expect that that would've been, you know, noted as a risk.

JAKE STURMER: A spokesman for Telstra confirmed the insecticide had been used, but says the telco stopped using the chemical well before the 1990s. Another spokesman for NBN Co referred the ABC back to Telstra and was trying to track down more information.

Jake Sturmer, Lateline.

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